Septic Arthritis: Symptoms, Causes, Treatment

One joint is often affected, but multiple joints or a prosthetic joint may be involved. It can resemble gout; delay risks cartilage damage and systemic infection.

Related reading: Distinguishing calcium-crystal arthritis.

Severe pain, swelling, warmth and restricted movement are typical; fever may occur. Absence of fever does not exclude infection, particularly in older or immunocompromised people.

Bacteria may reach the joint through blood, a wound or a nearby procedure. Less common organisms include fungi. Treatment depends on the organism, affected joint and overall condition.

Prosthetic joints, recent surgery, existing joint disease, immune suppression, diabetes and skin infections increase risk. Infection can also occur without these factors.

Prompt aspiration tests joint fluid for cells, crystals and organisms; blood cultures and imaging may help. Obtain samples before antibiotics when feasible, but never delay treatment in sepsis.

The team selects antibiotics using culture results and clinical findings, with needle, arthroscopic or surgical drainage. Duration and route vary. An infected prosthetic joint may need a distinct surgical strategy.

Permanent cartilage damage, impaired movement, bloodstream infection or bone infection can occur. Early treatment, follow-up and supervised rehabilitation reduce risk, but recovery varies.

Wound care, treatment of infections and sterile procedures reduce risk. Avoid injections into an unexplained inflamed joint and do not substitute leftover antibiotics for medical assessment.